1. Field of the Invention
The present invention relates generally to a projector, and more particularly, to a projector for displaying two different images by projecting different pieces of image information at different time points using a single optical module.
2. Description of the Related Art
A projector generally displays an image enlarged on a screen by projecting image information from an optical module to a screen separated from the optical module by a set distance. The size of an image displayed on the screen can be controlled according to the distance between the optical module and the screen. When a sufficient distance to the screen has been set, the projector can easily create a high-definition large screen irrespective of the size of the projector.
Recently, portable-size projectors have been commercialized and portable terminals such as mobile phones have been equipped with projectors. These devices are useful, for example, to office workers that are frequently out on business or in meetings.
The development trend of projectors is a dual-view function that enables simultaneous display of images on two or more screens using a single optical module.
FIG. 1 illustrates a conventional projector having a dual-view function, disclosed in U.S. Patent Publication No. 2009-0128716 to Nagashima et al, filed on Nov. 3, 2008. Referring to the reference numerals therein, the projector splits image information emitted from a 3-wavelength laser beam generator 350 into two paths through a beam splitter 383. First split image information is projected as a front image 132A on a screen 130 and second split image information is projected as a surface image 122A on a table 120.
The first and second image information is split from the same image information. Therefore, the images 132A and 122A projected onto the screen 130 and the table 120, respectively, are the same image. Compared to a projector that projects an image onto a single screen, the quality of the images projected onto the screen 130 and the table 120 is low and the projector is not optimally utilized.